Question

9^(x) +3^(x+1) -4=0 помогите плизз

Answer 1

$\9^{x} +3^{x+1} -4=0 \ (3^2)^x+3^xcdot3-4=0\ (3^x)^2+3cdot3^x-4=0\ (3^x)^2-3^x+4cdot3^x-4=0\ 3^x(3^x-1)+4(3^x-1)=0\ (3^x+4)(3^x-1)=0\\ 3^x+4=0\3^x=-4Rightarrow xin emptyset\\ 3^x-1=0\ 3^x=1\ x=0$